Fibre: The Nutrient Most Adults Aren't Getting Enough Of

Why So Many Adults Fall Short

Despite being widely available and relatively inexpensive, dietary fibre is one of the most consistently under-consumed nutrients in modern diets. Research from multiple European countries suggests that average adult intake sits at roughly half the recommended daily target. The explanation is straightforward: ultra-processed foods, refined grains, and convenience meals — which dominate many people's daily eating patterns — contain very little fibre.

White bread replaces rye. White rice replaces brown. Packaged snacks replace fruit and nuts. Each individual swap seems minor, but the cumulative effect across a day is a dramatic reduction in fibre. Understanding what fibre actually does — and why its absence matters — is the first step toward closing the gap. For a broader look at how overall eating patterns shape health outcomes, see why eating patterns matter more than individual foods.

What Fibre Does in the Body

Fibre's effects extend well beyond keeping digestion regular, though that alone is significant. Soluble fibre — abundant in oats, apples, lentils, and psyllium — dissolves in water to form a viscous gel in the gut. This gel slows the absorption of glucose into the bloodstream, helping to moderate blood sugar spikes after meals. It also binds cholesterol-rich bile acids, supporting healthy LDL cholesterol levels over time.

Insoluble fibre — found in wheat bran, vegetable skins, and whole grains — adds bulk and speeds transit through the colon, reducing the time that waste spends in the digestive tract. Beyond these mechanical roles, fibre fermented by gut bacteria produces short-chain fatty acids such as butyrate, which help maintain the intestinal lining and support immune function. This connection between fibre and the gut microbiome is an active area of nutritional research.

For context on how blood sugar dynamics relate to food choices, understanding the glycaemic index offers useful background — though fibre is only one piece of that picture.

“Dietary fibre is arguably the most neglected nutrient in discussions about public health. The evidence linking adequate intake to reduced risk of cardiovascular disease, type 2 diabetes, and colorectal cancer is among the most consistent in nutritional epidemiology.”

— World Health Organization, Global public health authority — dietary guidelines on fibre and non-communicable disease risk

Practical Ways to Eat More Fibre Every Day

Closing the fibre gap does not require radical dietary overhauls. Several small, consistent changes reliably increase daily intake:

• Switch to whole grain versions of bread, pasta, and rice. This single change can add several grams of fibre per day without altering meal structure.
• Add legumes regularly. A half-cup serving of cooked lentils or chickpeas provides around 7–8 grams of fibre. Stir them into soups, salads, or grain bowls.
• Keep the skin on vegetables and fruits where edible — much of the fibre is concentrated there.
• Snack on nuts, seeds, or fresh fruit rather than refined snack foods.
• Build meals around plants. Aiming for at least two to three different plant foods per meal naturally increases fibre variety and quantity.

Hydration matters here, too — fibre absorbs water, and adequate fluid intake helps it do its job without causing discomfort. For practical guidance on meeting daily fluid needs, see staying adequately hydrated.

It also helps to recognise when misinformation about food complicates decisions — common nutrition myths explores several widespread beliefs that can distort how people approach eating.

This article is for general informational and educational purposes only and does not constitute medical or dietary advice. For personalised guidance, consult a qualified healthcare professional or registered dietitian.